From owner-freebsd-hackers@FreeBSD.ORG  Mon Sep 26 18:15:26 2005
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From: Hans Petter Selasky <hselasky@c2i.net>
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Date: Mon, 26 Sep 2005 19:31:45 +0200
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Subject: bus-dma question
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Hi,

I see something suspicious on Amd64, when allocating small blocks of DMA-able 
memory:

bus_dmamap_load_callback: 0x0000000000caf200
                          ^^^^ this is physical address

QH(0xffffff0000caf200) at 0x00caf200:
   ^^^^ this is kernel address

Shouldn't kernel addresses always be different from physical addresses ?


When allocating larger blocks of memory I get, for example:

bus_dmamap_load_callback: 0x000000003bc50000

which seems correct.

--HPS